A simulation study on the performance analysis of the data link layer of IEC/ISA fieldbus

Fieldbus provides real-time data communication among field devices in the process control and factory automation systems. IEC and ISA recently approved the field bus standard for use in industrial control systems. The data link layer of IEC/ISA fieldbus provides token-passing and scheduling services for data transmission. This paper analyzes the performance characteristics of the IEC/ISA fieldbus. Especially the capabilities of the real-time data transmission and priority mechanism. In this study, a discrete-event simulation model of the data link layer of IEC/ISA fieldbus is developed. Using the simulation model, this study identifies tire network parameters that influence the performance of the data link layer, and investigates the delay performance with respect to the change of the network parameters. Based OM the simulation analysis, this study draws essential conclusions that should be consider rd in the network system design ar td operation of IEC/ISA fieldbus.